Sunday, November 7, 2010

In an important breakthrough for regenerative medicine, cells have been grown from human livers that function exactly like regular livers in a laboratory environment. It's in early stages, but this could be a huge step towards solving the transplant shortage.

Like pretty much all organ transplants, there are never even close to enough replacement livers for those who need them, and it can be an agonizing wait for patients and families as they hope to secure a donor organ. In theory, there's a better way to do this - grow replacement organs in labs, and then transplant those into the patients. That remains just a dream - but it now looks quite a bit more realistic after a breakthrough at Wake Forest's Institute for Regenerative Medicine.

Researchers there have engineered the first artificial, miniature livers that function just like their natural counterparts, at least in controlled laboratory conditions. The next step will be to see if the cells can continue to function properly when transplanted into animals. Even if these cells don't work when transplanted, this remains an important step in the right direction and should speed up the eventual creation of working artificial liver cells.

Whether such cells could then be put together to create entire replacement livers is another matter altogether, according to project director Shay Soker:

"We are excited about the possibilities this research represents, but must stress that we're at an early stage and many technical hurdles must be overcome before it could benefit patient. Not only must we learn how to grow billions of liver cells at one time in order to engineer livers large enough for patients, but we must determine whether these organs are safe to use in patients."

To create these miniature livers, the researchers took animal livers and treated them so that all their cells were removed, leaving only the collagen support structure behind. They then added immature human liver cells as well as cells vital for the creation of new blood vessels. After a week spent in a bioreactor that provided a constant stream of nutrients, the miniature livers displayed all the functions of a normal liver, not to mention continued cell growth.

This is very good news, and it's possible similar approaches could be used to engineer artificial kidneys and pancreases. It's an exciting step, but as Soker pointed out, there's still a long way to go. So if you're planning on massively mistreating your liver in the near future, don't count on one of these bioengineered organs coming to the rescue anytime soon.